Sheet metal brake



2 Sheets-Sheet l D l i INVENTOR B-YeQ/*ge hCEUcL/er Mofvf/Ly NM l G. H. RUCKER SHEET METAL BRAKE Filed July 20, 1927 May 26, 1931.

A TTORNE YS May 26 1931- G. H. RUCKER 1,806,986

` SHEET METAL BRAKE Filed July 20, 1927 2 Sheets-Sheet 2 FJ: 5 4- F1155- INVENTOR 6em/ge H. er

ATTORNEYS Patented May 26, 1931 UNITED STATES PA'TENT OFFICE GEORGE E. BUCKER, F STOCKTON, CALIFORNIA, ASSIGNOR, BY MESNE ASSIGNMENTS,

T0 CATERPILLAR TRACTOR CO., 0F SAN LEANDRO, CALIFORNIA, A CORBORAT'ION Ol' CALIFORNIA SHEET METAL BRAKE Application tiled July 20, 1927. Serial No. 207,118.

My invention relates to machines for forming sheet metal and relates particularly to machines for producing flanges and bends in metal sheets.

. My invention has for one of its objects the provision of a machine to be used in fabricating sheet metal shapes which are of a relatively complicated nature.

Another object of vmy invention is to pro- .vide means for forming simultaneously on a single sheet of metal a plurality of upturned flanges.

A further object of my invention is to provide a machine on which metallic anges of different contours can readily be formed.

A further object of my invention is to provide a metal forming machine in which metal sheets of varying thicknesses or gauges can easily be handled.

A still further object of my invention is to provide a sheet metal brake on which a plurality of removable and adjustable metal forming diesy are provided for increasing the versatility of the machine.

- My invention possesses other advantageous features, some of which with the foregoing will be set forth at length in the following description where I shall outline in full that form of the sheet metal brake of my invention, which I have selected for illustration in the drawings accompanying and forming part of the present specification. In saidv drawings I have shown one form of sheet metal brake embodying my invention, but it is to be understood that I do not limit myself to such form since the invention, as set forth in the claims, may be embodied in a plurality of forms.

In the drawings:

Fig. 1 is a front elevation of the sheet metal brake of my invention, with portions broken away to reduce the size of the figure.

Fig. 2 is a cross section of the metal brake of .my invention, the plane of section being indicated by line 2--2 of Fig. 1.

Fig. 3 shows in perspective a fragment of a metal sheet having a variety of flanges thereon formed by the brake of my invention.

Fig. 4 shows portions of the cooperating 50 fingers and dies to produce one type of flange.

Fig. 5 shows portions of fingers and dies arranged to produce a modified form of flange.

In its preferred form, the sheet metal brake of my invention preferably comprises a framework having an apron pivoted thereto yand carrying an adjustable die thereon adapted to cooperate with an adjustable finger secured to a leaf pivoted to the frame for holding and forming sheet metal.

In constructing the sheet metal brake of my invention, I preferably provide a frame 6 which can be fabricated of metallic shapes such as angles, to provide rails 7, supporting legs 8 and braces 9. The frame includes at each side a casting 11 of irregular shape which is riveted or bolted to the angles 8. The two castings 11 are tied together and the frame is strengthened by means of tie angles 12 and 13 which extend longitudinally of the brake and act as longitudinal spacers. Each casting 11 is provided with a horizontal bracket 14, preferably cast integrally therewith to support a table 16. A rail 17 is suitably secured to each of the castings 11 to provide an upper confine for the table and can be formed integrally with the casting 11 or preferably is detachably and adjustably secured thereto.

Toward the rear of the brake, each casting 11 is extended to provide a support for a leaf 15. The leaf preferably includes a pair of end plates 18 which can be of cast metal and each of which is provided with an apertured boss 19 journaled on a rod 21 suitably mounted in bosses on the two castings 11. Both plates 18 are thus coaxially pivoted to the frame 6. They are preferably tied together to move as a unit by an open box girder formed of two members 22 and 23. These can be of heavy sheet metal or can be cast plates which are suitably shaped to be secured to the end plates 18 by angles 24, flanges 26, and suitable securing means such as nuts and bolts or rivets. An extremely strong and rigid construction is thus provided as the box girder causes the two end plates 18 to move as a unit.

In the yuse of the brake, it is intended that a sheet of metal 27 be positioned on the table 16 and I have therefore provided means for holding the sheet in position on the table. Onthe girder 22, a projecting lip 28 is formed which extends longitudinally of the machine parallel to the axis of the pivot rod 21 and between the end plates 18. The projecting lip 28 is utilized as a convenient mounting for one or more fingers 29 for holding the metal sheet 27 on the table 16. Regardless of their number, the fingers 29 are preferabl alike in their major respects and each pre erably includes a shank 31 which extends under the member 22 and is downwardly curved to meet the table 16 at itsforward end. A hook 32 is formed integrally with shank 31 and overlies the projecting longia tudinal lip 28. To clamp the finger in place on the lip, a set screw 33 pierces the hook 32 and frictionally maintains the position of the finger 29. The set screw engagement permits the finger 29 upon suitable loosening of the fastening means to be shifted longitudinally of the machine to any desired degree or to be adjusted fore and aft within limits.

Means are provided for impelling the iingers 29 toward the table 16 in order to clamp a sheet of metal thereon. On each of the end plates 18, a forward boss 34 is formed in which a pin 36 is secured. The pins form journals for two similar links 37 disposedon opposite sides of the machine and engaging at their lower ends eccentrics 38 mounted to rotate in unison on a` through rod 39 journaled in the castings 11. As means for rotating the eccentrics 38, hand levers 41 project from suitable extensions on the eccentrics and the entire mechanism is preferably counterbalanced by weights 42 adjustably disposed on rods 43 also extending from the eccentrics. By manual rotation of the levers 41 the eccentric rod 39 is rotated, thereby causing the links 37 to lower the entire leaf 15. The fingers 29 are thereby lowered toward the table 16 and clamp in place a sheet of metal of any gauge or thickness which is disposed thereon.

The mechanism for forming the metal sheets into the desired shape is usually mount ed on the table 16. At the forward end of the table and at each side thereof, pivots are provided for supporting an apron. Each pivot preferably comprises a boss 44 forming the centrall portion of ahinge, the other member of which is a body 46 secured to a normally vertical plate 47 and pivotally connected to the boss 44 by a pin 48. The axes of each of the pins 48 preferably are in alinement and in addition they are also coincident with the upper and forward edge of the table 16.

On the apron I have provided means for forming a plurality of separate flanges on a metallic sheet and means which are removable and adjustable to vary the kind and contour of the work accomplished. The plate 47 carries at its upper edge a projecting tongue 49 extending parallel to the axes of the apron pins 48 and also parallel to a groove 5l cut in the forward face of the sheet. To the face of the sheet and also parallel with the groove 51 and tongues 49 is bolted a guide 52.l The tongue 49 and the guide 52 engage in suitable recesses cut in one or more dies 53 slidably mounted thereon and preferably retained in position frictionally by a set screw 54 running in the slot 5l.

The dies in their normal positions extend vertically and they are usually formed with their upper faces continuing the upper surface of table 16. When a metal sheet is held on the table 16 by means of the clamping fingers 29, the apron is rotated about its pivots 48 and the sheet metal is correspondingly bent into form by the dies. For rotating the apron, handles 56 are formed at the lower end of the sheet 47 and are conveniently shaped in the form of spheres. To counteract the weight of the apron and render it easily movable weights 57 are adjustably mounted on rods 58 secured to the bodies 46 and lying on the opposite side of the axis of pivots 48 from the major portion of the apron.

When metal sheets of extreme thinness are being worked, the leading edge of the finger 29 usually substantially coincides with the axis of pivot 48. With increasing thickness of the metal sheets and with varying shapes of flanges, it is in some cases desirable to have the leading edge of the finger 29 displaced somewhat from its axially coinciding position. I therefore provide means for displacing as a unit the table 16 and the apron attached thereto in a direction perpendicular to the longitudinal dimensions of the machine and perpendicular to the axes of pivots 21.

Preferably, the rails 17 are vertically adjustable so that the table 16 is freely slidable fore and aft between them and the supporting brackets 14. The table can then be moved into adjusted position and can be maintained in position by a suitable screw 59 engaging a threaded aperture 61 in the trailing edge of the table 16. The screw is preferably rotatably mounted in a bracket 62 fastened on the tie angle 12 and is confined in its axial translation by a crank 63 and a collar 64. Suitable manipulation of crank 63 propels or retracts table 16 with the apron attached thereto so that the axis of the pivots 48 is displaced with respect to the leading edge of fingers 29. Any relative adjustment of these parts can thus easily be attained.

It is not necessary that the fingers 29 and dies 53 be formed as disclosed in Fig. 2, but in order great-ly to extend the versatility of the machine and increase the variety of forms capable of being made on it, the fingers 29 preferably are provided with apertures 66 as disclosed in Figs. 4 and 5 to Which suitable detachable dies 67 can be secured by dowels 68. Corresponding changes can be effected in the dies 53 or which, being interchangeable, can be replaced by other dies 69 having cooperating contours in their effective surfaces. Various forms of removable dies 67 can be provided and suitable cooperating dies 69 can also be utilized so that, as shown in Fig. 3, a single sheet of metal, by the use of my machine, can be provided With the three diii'erent types of flanges disclosed therein. These are by no means the limiting number of variations possible with my machine inasmuch as the removable dies and lingers, their adjustability, particularly longitudinally of the machine, and their interchangeability render an almost infinite variety of shapes possible. Not only that, but it is also possible by the use of my machine to provide on a single sheet of metal a plurality of Widely varying forms and to turn up suitably several lips in the central portion of a sheet.

t will thus be appreciated that by using the same frame, table, apron and leaf, and simply by interchanging or altering the fingers and dies, I can adapt my machine to produce a great number of variations in sheet metal forms.

I claim:

1. A sheet metal brake comprising a frame, a table horizontally adjustable on said frame, an apron hinged to said table, a leaf hinged to said frame, and fingers on said leaf adapted to cooperate with said table to hold a metal sheet.

2. A sheet metal brake comprising a frame, a table movable in one plane with respect to said frame, an apron hinged to said table with the hinge axis parallel to said plane, dies on said apron, a leaf hinged to said frame With the hinge axis parallel to said plane, and fingers on said leaf. f

3. A sheet metal brake comprising a table, an apron hinged to said table and normally disposed perpendicularly thereto, a longitudinally movable die on said apron, a leaf normally movable with respect to said table,

`and a longitudinally movable finger on said leaf for cooperating with said die to form sheet metal.

4. A sheet metal brake comprising a slidpf i:longitudinally movable fingers on said 6. A sheet metal brake comprising a frame, hinges on said frame having their axes coinciding, a leaf mounted on said hinges and having an edge parallel to said axes, a plurality ofingers clamped on said edge and movable in the direction of said axes, a table mount-ed on said frame, means for moving said table in directions perpendicular to said axes, second hinges on said table having their axes coinciding and parallel to the axes of said first-named hinges, an apron mounted on said second hinges, and a plurality of dies mounted on said apron-and adjustable in the direction of the axes of said second hinges.

In testimony whereof, I have hereunto set my hand.

GEORGE H. RUCKER.

able table, a linger for holding a metal sheet on said table, an apron movable with respect to said table, and a plurality of longitudinally 'movable dies on said apron for forming said metal sheet.

5. A sheet metal brake comprising a frame, a table transversel adjust-able on said frame, means for adjusta ly positioning said table, a pair of hinges at the sides of said table, an apron mounted on said hinges, a plurality of longitudinally movable dies on said apron, a air of hinges at the sides of said frame, a eaf mounted on said hinges, and a plurality 

